Field of the Disclosure
The present disclosure relates to a display device, and more particularly, to a backlight unit and a display device including the backlight unit.
Description of the Background
In general, a liquid crystal display (LCD) device is a type of flat panel display that displays images using the electrical and optical characteristics of liquid crystal, which has intermediate properties between liquids and solids. Since the LCD device is thin and light compared to other display devices and the power consumption and the driving voltage of the LCD device are low, the LCD device has been widely applied and used in various industries.
Meanwhile, because the LCD device is a non-luminescent element that emits light due to external factors, the LCD device requires a separate light source. Accordingly, a backlight unit having a light source is provided on the rear surface of a liquid crystal panel to project light toward the front of the liquid crystal display device. The light is diffused while passing through a plurality of optical sheets, and is condensed by the liquid crystal panel, thereby being implemented as an identifiable image.
In general, the backlight unit of an LCD device is classified into an edge-type backlight unit or a direct-type backlight unit depending on the arrangement of a light-emitting lamp used as a light source.
The direct-type backlight unit includes a plurality of lamps, which are arranged in a row on the rear surface of a liquid crystal panel and directly projects light onto the front surface of the liquid crystal panel. The edge-type backlight unit includes a light source that is provided outside a light guide plate that guides light, in which the light emitted from the light source is incident on the entire surface of the liquid crystal panel using the light guide plate.
In the edge type backlight unit, since the light source is disposed at the edge of the light guide plate, one region of the light guide plate is located adjacent to the light source, and another region is located far away from the light source. Therefore, a large amount of light is supplied to the one region of the light guide plate, which is located adjacent to the light source, but a small amount of light is supplied to the other region, which is located far away from the light source. Thus, there is a problem in that the light is not uniformly emitted from the front surface of the light guide plate, and as a result, a portion is darker or brighter than the other portion, and dark portions, i.e. hot spots, occur.